WEDNESDAY, May 29 (HealthDay News) -- Three-quarters of doctors who responded to a survey about medical marijuana said they would approve the use of the drug to help ease pain in an older woman with advanced breast cancer.

In a February issue of the New England Journal of Medicine, doctors were presented with a case vignette, as well as arguments both for and against the use of medical marijuana. Doctors were then asked to decide whether or not they would approve such a prescription for this patient.

The results now appear in the May 30 edition of the journal.

Seventy-six percent of the 1,446 doctors who responded said they would give the woman a prescription for medical marijuana. Many cited the possibility of alleviating the woman's symptoms as a reason for approving the prescription.

"The point of the vignette was to illustrate the kinds of patients that show up on our doorstep who need help. This issue is not one you can ignore, and some states have already taken matters into their own hands," said Dr. J. Michael Bostwick, a professor of psychiatry at the Mayo Clinic in Rochester, Minn.

Bostwick wrote the "pro" side for the survey, but said he could've written the "con" side as well, because there are valid arguments on both sides of the issue.

"There are no 100 percents in medicine. There's a lot of anecdotal evidence that this is something we should study more. Forgive the pun, but there's probably some fire where there's smoke, and we should investigate the medicinal use of marijuana or its components," Bostwick said.

Marijuana comes from the hemp plant Cannabis sativa. It's a dry, shredded mix of the plant's leaves, flowers, stems and seeds. It can be smoked as a cigarette or in a pipe, or it can be added to certain foods, such as brownies.

The case presented to the doctors was Marilyn, a 68-year-old woman with breast cancer that had spread to her lungs, chest cavity and spine. She was undergoing chemotherapy, and said she had no energy, little appetite and a great deal of pain. She had tried various medications to relieve her pain, including the narcotic medication oxycodone. She lives in a state where the use of medical marijuana is legal, and asks her physician for a prescription.

Dr. Bradley Flansbaum, a hospitalist at Lenox Hill Hospital, in New York City, said he sided with the majority for this particular case.

"I think there's some context that needs to be considered," Flansbaum said. "This was a woman with stage 4 cancer who wasn't responding to [anti-nausea medications]. I'm not saying let's legalize marijuana, but this is a woman at the end of her life, so what's the downside, given that there might be a benefit. In a different situation, medical marijuana might not be so well embraced."

For his part, Bostwick said that while he approved the use of medical marijuana in this case, he feels it's important that the prescription of marijuana as medicine only be done within the confines of an already-established doctor-patient relationship.

"My concern is doctors who see someone once and give them a prescription for medical marijuana. That's bad medicine," Bostwick said.

While many physicians felt as if there was no harm in allowing the breast cancer patient to try marijuana to see if it helped, Dr. Gary Reisfield, who co-wrote the "against" side for survey, expressed concern about a patient with lung disease smoking marijuana.

"Marijuana smoke irritates the airways," he said. The smoke can also cause airway inflammation and symptoms of bronchitis, and decreases the ability of the lungs to fight off fungal and bacterial infections, said Reisfield, chief of pain management services at the University of Florida's department of psychiatry.

What's more, marijuana isn't as safe a drug as many believe it to be. "Heavy marijuana use is associated with numerous adverse health and societal outcomes including psychomotor, memory and executive function impairments; marijuana use disorders; other psychiatric conditions such as psychosis; poor school and work performance and impaired driving performance," he said.

Many of the physicians who responded pointed out that drugs already approved and in use also have the potential for addiction, such as narcotics. "Similar arguments could be made against alcohol, opiates and stimulants," Bostwick said.

For his part, Reisfield pointed out that there are two FDA-approved prescription cannabinoid pills -- dronabinol (Marinol) and nabilone (Cesamet) -- that don't begin working as quickly as smoked marijuana, but provide longer symptom relief without the high of marijuana. They also don't appear to have any addictive properties, he said.

What many doctors would like to see, according to the survey, is more evidence on the use of marijuana as medicine, so they could make a better-informed decision one way or the other.